Plots are an elegant and effective way to represent
data. At their best they encourage the reader and promote comprehension.
A graphical representation can give a far more intuitive feel to
the pattern of results in the study than a list of numerical data,
or the result of a statistical calculation. The temptation to exaggerate differences or relationships between
variables by using broken axes, overlaid axes, or inconsistent scaling
between plots should be avoided. A plot should be self-explanatory and not complicated. It should
make good use of the available space. The axes should be scaled
appropriately and labelled with an appropriate dimension. Plots are recognised statistical methods of presenting data and
usually require specialised statistical software to create them.
The statistical analysis and methods to generate the plots are as
important as the methodology of the study itself. The software,
including dates and version numbers, as well as statistical tests
should be appropriately referenced. Following some of the guidance provided in this article will
enhance a manuscript. Cite this article:
Over a 13-year period we studied all patients who underwent major hip and knee surgery and were diagnosed with objectively confirmed symptomatic venous thromboembolism, either deep venous thrombosis or non-fatal pulmonary embolism, within six months after surgery. Low-molecular-weight heparin had been given while the patients were in hospital. There were 5607 patients. The cumulative incidence of symptomatic venous thromboembolism was 2.7% (150 of 5607), of which 1.1% had developed pulmonary embolism, 1.5% had deep venous thrombosis and 0.6% had both. Patients presented with deep venous thrombosis at a median of 24 days and pulmonary embolism at 17 days after surgery for hip fracture. After total hip replacement, deep venous thrombosis and pulmonary embolism occurred at a median of 21 and 34 days respectively. After total knee replacement, the median time to the presentation of deep venous thrombosis and pulmonary embolism was 20 and 12 days respectively. The cumulative risk of venous thromboembolism lasted for up to three months after hip surgery and for one month after total knee replacement. Venous thromboembolism was diagnosed after discharge from hospital in 70% of patients who developed this complication. Despite hospital-based thromboprophylaxis, most cases of clinical venous thromboembolism occur after discharge and at different times according to the operation performed.
